The Washington Post reports that the United States is funding an underground construction project near an Israeli air base outside of Tel Aviv. Physically underground, the nature of the project also retains some mystery.

The project has the bizarrely nominated codename of “911”, the oft-used nomenclature of the Al Qaeda September 11th attacks in New York and Washington DC.

With the price-tag of $100 million, the secretive Site 911 plan is expected to take two years to roll-out, and is one of the largest construction projects to US Army Corps of Engineers has ever undertaken abroad.

The US has previously supported the Israeli Defense Force with various projects that help the IDF maintain its presence in the Occupied West Bank.

The underground complex is to be five stories ‘high’, with each of the first three floors approximately 41,000 square feet. Other details disclosed include smaller lower two floors designed as storage for 'equipment', according to a notice posted in the Corps magazine.

When questioned, the US said that it could not provide any information saying that only an official from the IDF was at liberty to answer any enquiry about Site 911.

Security will be tough at the new facility. The air-tight IDF lower fortress, complete with classrooms and auditorium, comes bolstered by shock-resistant doors and radiation screens.

According to the notice in the Corps publication, personnel working on building the project can only come from approved countries, including “the U.S., Canada, Western Europe countries, Poland, Moldavia, Thailand, Philippines, Venezuela, Romania and China.” Prospective job seekers from the Palestinian community also need not apply.

Other security stipulations include that the secretive bunker, “shall have one gate only for both entering and exiting the site” and “no exit or entrance to the site shall be allowed during work hours except for supply trucks.” Also, “the collection of information of any type whatsoever related to base activities is prohibited.”

Security staff will have to be Israeli citizens with previous experience in the Israeli Air Force.